THE EVOLUTION OF THE PBIMATBB 323
of the teeth, so the dental characters of the modern Lemurs differ greatly from those of the Notharctidse.
The Notharctidse were closely related to the Lemu-roidea of the Family Adapidse, which migrated to Europe in Eocene times. The actual place from which they started is not known, but it was near America, possibly in the northern circumpolar land.
The Family Anaptomorphidse contains several Tarsioids, which can be arranged in the genera Anaptomorphus, Hemiacodon, Omomys, Tetonius, Uin-tanius and WashaJcius. The remains are scanty, but they show that the animals were small and variously 'specialized. They differed from the Notharctidse in the immense orbits, the expanded cranial cavity and the reduced muzzle. So we can assume that these changes were accompanied by the same alterations in the visual apparatus which distinguish Tarsius from a Lemur (see page 34). They resemble Tarsius in many ways, but no species hitherto discovered is ancestral to it.
Special interest is attached to Anaptomorphus homun-culus, which is really a Tetonius. Cope (507) and others regarded it as ancestral to the Apes and Man. The dental formula, according to Matthew, is I^C^PMfMf. The canine teeth were well marked according to reconstructions, and the molar teeth are transversely expanded. The auditory bullse are inflated and closely applied to the basis cranii; and the cranial cavity is about the same size as that of Tarsius. The importance of Cope's observation that liovnunculus was the most Ape-like Lemuroid discovered up to that time (1885) has been enhanced by subsequent investigations, which, have proved that the Anaptomorphidse gave riie to the